Valves



Sept. 8, 1959 o. N. RODGERS ET AL 2,

VALVES Filed June 21, 1954 s Sheets-Sheet 1 029$ /Ve0 Ron yen:

Wc7//c7ce f? O/ao/v INVENTORS BY WM W A TTOE/VEY Sep 1959 o. N. RODGERSETAL 2,903,235

VALVES Filed June 21, 1954 s Sheets-Sheet 2 0kg; Ned Rod 79A;

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IN VEN T0 A TTO/gA Ey Sept. 8, 1959 o. N. RODGERS ET AL 2,903,235

VALVES Filed June 21, 1954 3 Sheets-Sheet 3 Wa/ e O/J0/7 ENTORS BY mUnited States Patent O VALVES Otis Ned Rodgers and Wallace F. Olson,Oklahoma City, Okla, assignors, by rnesne assignments, to American Iron& Machine Works Company, inc, Oklahoma City, Okla, a corporation ofDelaware Application June 21, 1954, Serial No. 438,122

4 Claims. (Cl. 251-332) This invention pertains to valves and moreparticularly to valves incorporating an element of low elastic modulusmaterial compared to steel and other hard metals, e.g. a rubber-likeflowable material such as neoprene or hycar, for sealing between a valveseat and valve closure. The seat and closure will usually be made ofsteel or other hard material, though in some cases the seat or closureor both may incorporate softer materials supported by other harder andstronger material.

The invention is particularly suited for use in connection with valvesfor slush pumps used to circulate fluid through an earth hole in welldrilling. Such pumps operate at high pressure, e.g. several thousandpounds per square inch and the fluids pumped are highly abrasive,usually carrying a considerable amount of suspended sand. To meet suchconditions a type of valve now in common use in slush pumps comprises asteel base member providing a means for closing at least most of theopening controlled by the valve, a sealing element carried by the basemember for sealing between the base memher and valve seat, and a capmember over the sealing element, the flow of fluid controlled by thevalve being in the direction generally from the cap member to the basemember. The sealing element engages the base member and valve seat onthe same sides with respect to the direction of fluid flow, which in theusual case is the upstream side of each. The cap member serves to retainthe sealing element in position, especially when the valve is not in thefully closed position. The cap and base members, together with the valveseat, largely confine the sealing element so that it will not bedeformed beyond its yield point when exposed to full pressuredifferential in the closed position of the valve.

The sealing element is made of low elastic modulus material so that itwill, under pressure when the valve is closed, flow into all the smallirregularities in the surfaces of the valve seat and base member incontact therewith to seal therewith and hence form a seal therebetween.The sealing element will also fill the irregularities of the cap memberand seal therewith, thereby forming a seal bridging the cap member andvalve seat. In some cases the base member and cap member may beintegral. A general statement of the function of the sealing element isthus to seal with and between the valve seat and the valve closure.

The sealing element will not only flow to fill the irregularities in thevalve closure and seat but it will also flow into the crevice at thejuncture of the valve closure and seat, e.g. between the base member andvalve seat. This crevice will be larger than the surface irregularitiesof the valve seat and closure, especially after the valve is worn, sothat the strain or deformation of the material required to fill thecrevice will be much larger. The stress on this bridging portion will beproportionately higher and may be close to the elastic limit.

deformation in valve closed position, so that every time the valve movesbetween open and closed position there is a stress reversal.

The bridging portion of the sealing element in many types of valves willbe at a place where the direction of the surface of the element changes,sometimes sharply. Often the valve closure element, e.g. the base memberthereof, will have a sharp corner adjacent the bridging portion of thesealing element. This not only provides a sharp transition fiomsupported to unsupported condi tion of the sealing element but mayactually form a knife edge tending to cut it.

For the above outlined reasons and perhaps others, it has been foundthat the bridging portion of the sealing element of a slush pump valveis often the first point of failure thereof after a period of use. It isthe principal object of this invention to eliminate or retard suchfailure so as to prolong the life or" the sealing element.

Other objects and advantages of the invention will appear from thefollowing description of a preferred embodiment of the invention andseveral modifications thereof, reference being made to the accompanyingdrawings in which Figure l is a vertical section through a slush pumpvalve and seat showing a preferred embodiment of the invention;

Figure 2 is a bottom view, partly in section, of the sealing elementshown in Figure 1;

Figure 3 is a plan view of the clamp shown in Figure 1;

Figures 4-14 are vertical sections through portions of valves and seatssimilar to that of Figure 1 and showing modifications thereof.

Referring now to Figure 1 there is shown a portion of a pump body 10having a removable and replaceable valve seat ring 11 inserted in anopening therein. The valve seat ring has a conical surface 12 forming aseat and a plurality of webs 13 forming a spider supporting a lowervalve stem guide bearing 14.

The opening through the valve seat ring is shown as closed by a valvecomprising a stem having a lower portion 20 provided with a plurality ofrubberlike wear rings 21 thereon slidably disposed in bearing 14, and anupper portion 22. A disc or flange 23 integral with the valve stem has aplane bottom surface 24 spaced slightly above the webs 13 and bearing14, a conical outer peripheral edge 25 adapted to seat on surface 12 ofthe seat ring, and a conical upper surface 26 interrupted by a squarecross-section annular bead 2'7. Flange 23 is the base member of thevalve closure.

On top of flange 23 is disposed a sealing element 3i which may be madeof natural or synthetic rubber and may be suitably modified withfillers. For example the sealing element may be made of neoprene orhycar and desirably has a hardness in the range of to 75 durometer,preferably durometer.

The lower surface 31 of the sealing element is conical to engage surface26 of the flange 23, and have a square section annular channel 32 toreceive bead 27.

The sealing element 31 is a ring having a central cylindrical opening 33to slide over an enlarged portion 34 of the valve stem. The uppersurface 35 of the sealing element 30 is plane and the thickness of theelement is such that slight axial compression is required to bringsurface 35 even with plane shoulder 36 on the valve stem. Thiscompression is achieved by a cap member in the form of a plate orremovable flange 37 held in place by a U shaped clamp 38 slipped under adownwardly facing shoulder 39 on the valve stem and retained by a pin 40(see Figure 3).

Sealing element 30 has a flaring peripheral surface 50 adapted tocontact surface 12 of the valve seat ring. When unstressed, surface 50is conical and forms a continuous extension of surface 25 of the flange23. When the sealing element is compressed by plate 37 the surface 50bulges out slightly as shown.

Sealing element 36 has a conical peripheral surface 51 flaring oppositeto surface 50 joining surfaces 50 and 35, the juncture between surfaces50 and 51 being rounded asshown at 52, portion 52 extending slightly outover the upper plane surfaces 53 of the seat ring.

Sealing element 3t has incorporated therein at the bridging portion 60 areinforcement means 61. This reintorcement means increases the tensilestrength, the elastic modulus and the surface hardness at this point.Although it must be close to the surface to effect these results, itmust be disposed beneath the surface, as shown, in order not to impairthe sealing qualities of the element.

Preferably the reinforcement means 60 comprises an element such as atvulcanized into place. Element 61 may be in the form of a plurality offilaments parallel or random stacked, or in the form of a cloth made ofindividual filaments felted or woven or otherwise integrated, or in theform of a continuous sheet, and may be made of any of a variety ofmaterials such as cotton, linen, nylon, fibre glass, steel, copper,bronze. Canvass is a suitable material as shown best in the broken awaysection in Figure 2.. The surfaces of the component sheets of thereinforcing means, whether they be canvass, metal, or other material,extend parallel to the adjacent surfaces of the sealing element where itbridges between valve seat and closure.

As shown in Figure l, the reinforcing means preferably not only extendsover the bridging portion 60 of the seating element 23 but extends overthe portion that engages head 27. This reinforces the sealing element atits point of engagement with head 27 where it is also subject to severestresses, the head 27 and channel 32 interlocking and preventing thesealing element from pulling away from enlargement or hub 34 under fluidpressure. The reverse bends of the reinforcement as it passes aroundchannel 312 and head 27 also lock it in place in the sealing elementpreventing it from pulling loose.

Referring now to Figures 4 through 14, in each figure the valve seatring base member, cap member, sealing element, and reinforcing means aregiven the same numbers as the like parts in the Figure 1 embodiment,from which their construction will be readily understood.

It is to be noted that it is not desirable to reinforce the sealingelement throughout, for this would increase its hardness and strengthand resistance to cold flow under pressure to such an extent that itwould no longer perform its scaling function. The sealing element as awhole should have the desirable flow characteristics of natural orsynthetic rubber unhampered by any reinforcing means.

While a preferred embodiment of the invention and a number ofmodifications thereof have been shown and described, many modificationsthereof can be made by one skilled in the art without departing from thespirit of the invention, and it is intended to protect by Letters Patentall forms of the invention falling within the scope of the followingclaims.

We claim:

1. A valve sealing element adapted to be mounted with its axis in avertical plane comprising a ring made of vulcanized rubber compound, thebottom face of the ring being dished inwardly providing a base plateengaging portion, the lower outer periphery of the ring flaring upwardlyproviding a seat engaging portion, said ring including fabricreinforcement means just beneath its surface at the juncture of saidseat engaging and base plate engaging portions, the hardness of saidring being in the range of 65 to 75 durometer except at said fabricreinforced juncture where it exceeds 75 durometer in hardness, saidreinforcing means comprising canvass sheets disposed with their surfacesgeometrically similar to the outer surfaces of the ring adjacentthereto, the edges of the canvass lying beneath the outer surface of thering.

2. A valve device including a metal seat with an opening therein and asubassembly comprising a valve closure means large enough to close saidopening, the outer periphery of said closure means providing acontinuous rigid metal surface whose edge is contiguous with said metalseat when the valve member is in closed position, and a sealing elementof rubber-like material disposed to seal with said closure means andseat, sealing with both said seat and closure means on the same sidesthereof with respect to flow through said opening, and to bridge thejuncture between said seat and said outer periphery of said closuremeans the portion of said sealing element that seals with said seatextending beyond, said outer periphery of said closure means, saidsealing element having reinforcing means at the bridging portion thereofto decrease the elastic modulus and increase the strength of the sealingelement at that portion, said reinforcing means comprising sheetmaterial embedded in said sealing element close to but beneath thesurface thereof that is adjacent said outer periphery of said closuremeans and said seat when said subassembly is in closed position, thesurfaces of said sheet material being disposed parallel to the surfaceof said sealing element adjacent said bridging portion and the portiontherebeyond where said sealing element engages the seat when the valvesubassembly is in closed position, the outer edges .of said sheetmaterial terminating beneath the surface of said resilient material, thereinforcing means being free from exposure to frizzing and frazzling atthe seating portion of the sealing element, the bond between saidreinforcing means and the remainder of the sealing element beingsubjected primarily to compression and transverse bending moment whenloaded and free of direct pulling apart stresses, and the entire surfaceof the seating portion of the sealing element being free to flow intosealing engagement with said seat.

3. A valve including a body having an opening therethrough providing :aninlet and outlet and having a valve seat therearound and a valve headcomprising a .valve closure including a base member and a cap member,the outer periphery of said base member providing a continuous rigidmetal surface whose edge is contiguous to said valve seat, and a sealingelement disposed between said base member and cap member adapted to sealwith said closure and said seat on the same side of said seat and basemember as said cap member and to bridge between said seat and basemember, said periphery of the base member being conical flaring towardsaid cap member and the upper surface of said base member being conicalflaring away from said cap member, the periphery of said sealing elementbeing generally conical and forming 'a continuation of said conicalperiphery of the base member, the lower surface of the sealing elementbeing conical correlative to said upper conical surface of said basemember, said valve seat having an inner periphery that is conicalflaring in the same direction as the peripheries of said base member andsealing .element, said sealing element comprising a ring of rubber-likematerial havinga fabric reinforcing means just below the surface at theportion thereof at the juncture of said conical surfaces thereofopposite the juncture of said conical surfaces of said base member, saidreinforcing means being disposed and adapted to resist deformationandcold flow under pressure of said bridging portion into the spacebetween closure andseat, said reinforcing means comprising sheetmaterial whose surfaces lie parallel to the adjacent conical surfaces ofsaid sealing element on both sides of said juncture thereof, theperipheral outermost portions of said sheet material terminating withinsaid sealing element beneath the surface thereof the rubberlike materialof the sealing element covering the fabric ends to prevent; 'whiskeringthereof and the fibres of the reinforcing material lying just beneaththe surface of the sealing element parallel to the surface resistingflow thereof into the crevice at the juncture of the valve seat and saidbase portion.

4. A valve subassembly comprising a valve closure means having thegeneral shape of a disc having two faces facing generally in oppositedirections relative to the disc axis, the outer periphery of saidclosure means disc providing a continuous rigid metal surface, and asealing element of rubber-like material having a portion thereof with asurface disposed on one of said faces of said closure disc to sealtherewith and having a portion extending beyond said outer periphery ofthe disc forming a continuous resilient sealing surface contiguous withsaid outer peripheral surface of the closure disc, said sealing surfaceof said sealing element and the surface of the first said portion ofsaid sealing element that seals with said one face of the disc bothfacing generally in the same direction relative to said disc axis, theportion of said sealing element adjacent the juncture of said peripheralsurface and the overhanging portion of said sealing element forming abridge between said overhanging portion of the sealing element and saidportion thereof disposed on said disc, said sealing element havingreinforcing means at the bridging portion thereof to decrease theelastic modulus and increase the strength of the sealing element at thatportion, said reinforcing means comprising sheet material embedded insaid sealing element close to but beneath the surface thereof that isadjacent said outer periphery of said closure means disc and saidsealing surface of said sealing element, the surf-ace of said sheetmaterial being disposed parallel to the surface of said sealing elementadjacent said bridging portion and said portion therebeyond that formssaid sealing surface, the outer edges of said sheet material terminatingbeneath the surface of said resilient material, the reinforcing meansbeing free from exposure to frizzing and frazzling at said sealingsurface of the sealing element, the bond between said reinforcing meansand the remainder of the sealing element being subjected primarily tocompression and transverse bending moment but free of direct pullingapart stresses when subject to fluid pressure parallel to said axis andsaid entire sealing surface of said overhanging portion of the sealingelement being free to flow under said pressure.

References Cited in the file of this patent UNITED STATES PATENTS1,352,735 Egerton Sept. 14, 1920 1,781,129 Sexauer Nov. 1 1, 19301,890,247 Dieterich Dec. 6, 1932 2,093,662 Steirly Sept. 21, 19372,457,492 Raybould Dec. 28, 1948 2,495,880 Volpin Jan. 31, 19502,605,080 Rea July 29, 1952 2,718,373 Henry Sept. 20,, 1955 2,745,631Shellman May 15, 1956

